Choi R C, Yam S C, Hui B, Wan D C, Tsim K W
Department of Biology and Biotechnology Research Institute, The Hong Kong University of Science and Technology, Kowloon, China.
Neurosci Lett. 1998 May 22;248(1):17-20. doi: 10.1016/s0304-3940(98)00320-6.
Several lines of evidence suggest the non-cholinergic functions of acetylcholinesterase (AChE) in promoting neurite outgrowth of cultured neurons and in inducing the postsynaptic specializations of developing neuromuscular junctions. In order to support the hypothesis, a cholinergic synapse-forming cell line NG108-15 was over-expressed with chick AChE by cDNA transfection. The transfected NG108-15 cells secreted a approximately 105-kDa protein, recognized by anti-AChE antibody in Western blot analysis, corresponding to the chick AChE catalytic subunit. Over 80% of the recombinant enzyme were secreted into the conditioned medium and they were enzymatically active. In the NG108-15 cell-muscle co-cultures, the AChR-aggregating activity of NG108-15 cells was increased by the over-expression of AChE. The increase in AChR-aggregating activity of the transfected NG108-15 cells paralleled with the increase in agrin and neurofilament expression of the transfected cells as determined by their corresponding antibodies. However, the intracellular cAMP level remained unchanged in the AChE over-expressed NG108-15 cells. These results support the hypothesis that AChE could play a role in promoting neuron differentiation.
多条证据表明乙酰胆碱酯酶（AChE）具有非胆碱能功能，可促进培养神经元的神经突生长，并诱导发育中的神经肌肉接头的突触后特化。为了支持这一假设，通过cDNA转染使胆碱能突触形成细胞系NG108-15过量表达鸡AChE。转染后的NG108-15细胞分泌出一种约105 kDa的蛋白质，在蛋白质印迹分析中可被抗AChE抗体识别，对应于鸡AChE催化亚基。超过80%的重组酶分泌到条件培养基中，且具有酶活性。在NG108-15细胞与肌肉的共培养物中，AChE的过量表达增加了NG108-15细胞的AChR聚集活性。转染后的NG108-15细胞AChR聚集活性的增加与转染细胞中集聚蛋白和神经丝表达的增加平行，这是通过相应抗体测定得出的。然而，在AChE过量表达的NG108-15细胞中，细胞内cAMP水平保持不变。这些结果支持了AChE可能在促进神经元分化中发挥作用这一假设。
